Adjustable transmission for airplane motors and the like



April 1941- J. HLASNEY, JR 2,237,934

I ADJUSTABLE TRANSMISSION FOR AIRPLANE MOTORS AND THE LIKE Filed March 22, 1940 2 Sheets-Sheet 1 I LIE-.E- INVENTOR ATTO R N EY April 1941- J. HLASNEY, JR 2.237.934

ADJUSTABLE TRANSMISSION FOR AIRPLANE MOTORS AND THE LIKE Filed March 22, 1940 2 Sheets-Sheet 2 INN llnll INVENTOR Johnlildsrgey bt I tures of the invention are Patented Apr. 8, 1941 r UNITED STATES PATENT OFFICE ADJUSTABLE TRANSMISSION FOR Am- PLANE MOTORS AND THE LIKE John Hlasney, J r., New York, N. Y.

Application March 22, 1940, Serial No. 325,305

9 Claims. .gcl. 123-48) This invention relates tonew and useful improvements in a transmission construction for multi-cylinder engines.

The invention has for an object to construct the transmission for a multi-cylinder engine or;

other engine in a manner so that when required, adjustments may be made to make theengine develop more than just one maximum H. P. When a greater amount of H. P. output is desired it is proposed that the transmission be adjusted to give a greater capacity in the combustion chamber or chambers so that a larger amount of fuel mixture will be consumed. Therefore the weight per H. P. of the engine will lighten. When a smaller output ofH. P. is desired the transmission may be adjusted; to reduce the combustion chamber volume of the cylinders. There will then be a 'smaller maximum fuel consumption,

a smaller maximum piston displacement, and a larger weight per H. P.

More specifically, the invention contemplates the provision of an improved transmission constructionwhich may be used in conjunction with the cylinders of an engine to vary the H. P. characteristics thereof by increasing or decreasing the volume of the combustion chamber.

Still further the invention resides in the specific transmission construction illustrated and described. l i

For further comprehension of the invention,

and of the objects and advantages thereof, ref- I erence will be had to thefollowing description terial part of this disclosure:

Fig. 1 is a transverse sectional view of a multicylinder engine with a transmission constructed according to this invention.

Fig. 2 is a fragmentary sectional view on the line 2-2 of Fig. 1.

Fig. 3 is a perspective view of the central portion of Fig. 2 looking in the direction of the line 3-3 thereof. Fig. 4 is a perspective view of the parts shown :in Fig. 3 with the front disc removed and with the connecting rods removed.

Fig. 5 is a fragmentary perspective view of the lower end of one of the connecting rods.

Fig. 5Aisa fragmentary perspective View of the lower end of the connecting r carrying the master element. l

p g;eisapers-pective view oi the-front disc.

Fig. 7 is a sectional view taken on the line 1-4 of Fig, 4.

Fig. 8 is a transverse sectional view taken on the line 8-8 of Fig. 7 illustrated with the connecting rods in specific relation thereto.

Fig. 9 is a view similar to Fig. 8 but illustrating the connecting rods in different position.

Fig. 10 is a front view of the front disc of a transmission constructed according to a modification of this invention.

The adjustable transmission construction for varying the combustion space of an engine, according to this invention, includes a crank I0. A disc II is freely mounted on the pin Ill of the crank. A circular member, consisting of sections I2, is freely mounted on the crank pin Ill The disc II is formed with a plurality of radial slots IS. A friction element I4 is interposed between the disc II and the circular member l2 for frictionally connecting these partsvso that they have a tendency to maintain relatively fixed positions,

and when turned out of these fixed positions they will maintain the new positions.

A plurality of connecting rods [5 for the pistons 16 of an engine having cylinders ll, have forked inner ends l5 straddling the edge of the circular member I2. One of the fingers [5- of each connecting rod is provided with a protain the disc, II in its proper position relative to said connecting rod. The slot [3' into which this rectangular. element l9 engages, is also longer thanthe other slots so as not to interfere with the throw of the piston.

A pin 20 for each of the connecting rods I5 is mounted on the circular member l2 and project through arcuate slots 2| formed in the disc ll. These pins and slots act to limit the relative turning of the disc. and circular member with respect to each other a described. to be hereinafter further There is a cam 23 for each connecting rod I5. These cams are mounted on the circular member 12. Specifically, the cams are arranged between the section of the circular member. Each cam 23 1s p1votally supported by a pin 24, which passes through the section of the circular member l2 A coil spring 25 is arranged coaxial of each pin 24 within acavity 26, formed in. one face of the cam 23. These springs act between the cams and the circular member for normally resiliently urging the cams into a neutral position. Each cam 23 is in the form of a disc having a concaved edge portion 23 at one side having a radius equal to the length of the connecting rod. The normal position of the cam is one in which this concaved side 23 extends outwardly. The cams 23 are limited from turning through too great an amplitude by pins 21 projecting from each cam, and engaging arcuate slots 28 in the circular member l2.

The arrangement permits each cam 23 to pivot in one direction or the other a limited amount only.

When the pins 20 are at one of the ends of the slots 2|, the connecting rods I5 will be rested directly upon the concaved faces 23 of the cams 23. In these positions the connecting rods I5 cannot move inwards of the slots I3, since they are resting on the cams 23. When the circular member I2 is turned relative to the disc II, the

connecting rods I5 will slip off from the cams 23 and assume positions as illustrated in Fig. 9, that is, between the cams. .In 'these positions the connecting rods I5 may move inwards and. outwards as limited by theradial slots I3.

In the latter positions of the connecting rods I5, the stroke of the piston will be smaller than when the connecting rods are in their initial positions. This will be understood by realizing that as the crank I rotates the connecting rods I will be forced. outwards a distance which is determined by the'relative .positions of the master connecting rod of the disc I I. If the connecting rods I5 are held in extended position by the cams 23, then the pistons I6 will move through a relatively greater distance than would be the case if the connecting rods I5 are off of the cams, and the elements I9 are riding in the slots I3.

A means is provided externally of the engine, which is adapted to shift the circular member I2 relative to the disc II. This means comprises a pair of cams 40 which extend in opposit directions from the crank pin Ill of the crank ID.

One cam 40 is fixedly mounted upon the crank pin Ill adjacent the-front face of the disc I I, and extends in one direction. The other cam 40 is fixedly mounted upon thepin Ill adjacent the back face of the circular member l2, and is extended in a direction opposed to the direction in which the first-mentioned cam extends.

This latter means further includes a pair'of stub shafts 4| arranged onopposite sides of the crank 10, and extending from the interior to the exterior of the case of the engine. Mounted upon each of the stub shafts 4| there is-a cam 42,-and each of the earns 42 is in alignment with one of the cams 40. The arrangement is such that the stub shafts may be turned to'extend the cams 42 into the path of motion of the cams 40 which are fixed to the crank pin III and move in a circle about the center turning point of the crank A synchronized means is provided for causing one of the cams 42 to be extended into the path of motion of its respective cam 40, while the other cam 42 is out of the path of motion of its respective cam 40. To accomplish this a sprocket wheel 43 is mounted upon the outer end of each of the stub shafts 4|. A chain-engages over the sprocket wheels 43 for connecting the stub shafts 4| together for simultaneous movement. One of the stub shafts 4I-has a second sprocket wheel 45 over which asecond .chain 43 engages. This chain'46 extends downwards -and connects with a manual means (not shown in drawings) for causing the stub shafts 4| to be simultaneously moved to properly extend and retract the projections 42 into and out of the path of motion of the cams 40. When the cams 42 are extended towards the crank I0, their respective cams 40 will strike thereagainst and turn the pin l0. Due to the fact that the circular members I2 are fixed to the pin Ill while the disc II is free, the circular members I2 will be caused to be similarly turned relative to the disc II.

In Fig. 1 the cam 42 at the left is in its operative position, while the one at the right is in its inoperative position.

In Fig. 10 another form of the invention has been disclosed. This distinguishes from the prior form in an arrangement by which the operative lengths of the slots I3 in the disc I I may be controlled. According to this form of the invention each slot I3 is provided with an adjustment screw 34 adjustably mounted upon the periphery of the disc II, and extending into the outer end of the slot I3. Each slot I3 is provided with an adjustment screw 35 upon its inner end. This latter adjustment screw is provided with a locking nut 36. The former adjustment screws 34 are provided with looking nuts 31. The elements I9 working in the slots I3 will be limited in their amplitude of possibl travel. With this arrangement it is possible to adjust th engine to different amounts of piston displacements when required.

While I have illustrated and described thepreferred embodiments of my invention, it is to be understood that I do not limit'myself to the precise construction herein disclosed, and the right is reserved to all changes and modifications coming within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent is:

1. A device for varying the combustion space of a multi-cylinder engine, comprising a crank, a circular member on said crank, a disc free on said crank and'havinga plurality of radial slots and fric-tionally connected with said circular member, a plurality of connecting rods ;for the pistons of said engine and having forked inner ends straddling the edge of said circular member, and projecting elements engaging in said radial slots, means for relative partial rotation of said circular member and disc, and a cam for each connecting rod mounted on said circular member and against which said connecting rod abuts, and in one relative position of said circular member'and disc serving to hold th connecting rod and piston extended for minimum combustion space, and .another :position permitting the connecting rod and :pi's'to'n to assume a position for maximum combustion space.

2. A device for varying the combustion space of a multi-cylinder engine, comprising .a, crank, a circular member on said crank, a discfreeon said crank and having a plurality of radial slots and frictionally connected with said circular-memher, a plurality of connecting rods for the pistons of said engine and having forked inner ends straddling the edge of said circular member, and projecting elementsengaging in said radial slots, means for relative partial rotation of said circular member and disc, and a cam for each "connecting rod mounted on said circular member andagainst which said connecting rod abuts, and

in onerelative position of said circular member and disc serving to hold the connectinglrod'and piston extended for minimum'combustion space,

'and another position permitting the connecting "rod and piston to assume a'position for maximum combustion space, said circular member compris- 'i'nga-pairsof adjacent sections. x

, 3. A devicefor varying the combustion space i of a multi-cylinder engine, comprising acrank, a circular member on said crank, a disc free on" said crank and having a plurality of radial 3 slots, and frictionally connected with said cirjcular member, a plurality of connecting rods for the pistons of said engine and, having forked inner ends straddling the edge of said circular. member, and projecting cylindrical 1 elements engaging in all except one of said slots, a rectangularelemen-t being onone of said forked another position permitting the connecting rod and piston to assume a position for maximum combustion space, said circular member comprising a pair of adjacent sections, said cams being located between said sections.

1 4. A device for varying the combustion space of a multi-cylinder engine, comprising a. crank,-v

slots, means for relative partial rotation of said circular member and disc, and a cam for each connecting rod mounted on said circular member and against which said piston rod abuts, and in one relative position of said circular member and disc serving to hold the connecting rod and piston extended for minimum combustion space, and another position permitting the connecting rod and piston to assume a position for maximum combustion space, said circular member comprising a pair of adjacent sections, said cams being located between said sections, each cam being pivotally supported and mounted between said sections.

5. A device for varying the combustion space of a multi-cylinder engine, comprising a crank, a circular member on said crank, a disc free on said crank and having a plurality of radial slots and frictionally connected with said circular member, a plurality of connecting rods for the piston of said engine and having forked inner ends straddling the edge of said circular member and projecting elements engaging in said radial slots, means for relative partial rotation of said circular member and disc, and a cam for each connecting rod mounted on said circular member and against which said connecting rod abuts, and in one relative position of said circular member and disc serving to hold the connecting rod and piston extended for minimum combustion space, and another position permitting the connecting rod and piston to assume a position for maximum combustion space, said circular member comprising a pair of adjacent sections, said cams being located between said sections,

i each cam being pivotally supported and mounted between said sections, each cam being urged into a neutral position by a spring coaxial with the 'cam pivot and acting between the cam and f of said sections.

'6. A device for varying the combustion space of a multi-cylinder engine, comprising a crank, a circular member on said crank, a disc free on said crank and having a plurality of radial slots and frictionally connected with said circular member, a plurality of connecting rods for the piston of said engin and having forked inner ends straddling the edge of said circular member and projecting elements engaging in said radial slots, means for relative partial rotation of said circular member and disc, and a cam for each connecting rod mounted on said circular member and against which said connecting rod abuts, and in one relative position of saidcircular member and disc serving to hold the connecting rod and piston extended for minimum combustion space, and another position permitting the connecting rod and piston to assume a position for maximum combustion space, and circular member comprising a pair of adjacent sections, said cams being located between said sections each cam being pivotally supported and mounted between said sections and provided with a projecting pin, each cam being urged into a.

neutral position by a spring coaxial with the cam pivot and acting between the cam and one of said sections, said pin projecting from each cam and working in the slot in one of the sections whereby to limit the positions of the cam.

7. A device for varying the combustion space of a multi-cylinder engine, comprising a crank, a circular member free on said crank, a disc free on said crank and having a plurality of radial slots and frictionally connected with said circular member, a plurality of connecting rods for the pistons of said engine and having forked inner ends straddling the edges of said circular member and projecting elements engaging in said radial slots, means for relative partial rotation of said circular member and disc, and a cam for each connecting rod mounted on said circular member and against which said connecting rod abuts, and in one relative position of said circular member and disc serving to hold the connecting rod and piston extended for minimum combustion space, and another position permitting the connecting rod and piston to assume a position for maximiun combustion space, each cam being in the form of a disc having a concaved area at one side, the connecting rods being engageable with this concaved area on one of the rc'lelative positions of said circular member and 8. A device for varying .the combustion space of a multi-cylinder engine, comprising a crank, a circular member on said crank, a disc free on said crank and having a plurality of radial slots and frictionally connected with said circular member, a plurality of connecting rods for the pistons of said engine and having forked inner ends straddling the edge of said circular member and projecting elements engaging in said radial slots, means for relative partial rotation of said circular member and disc, and a cam for each connecting rod mounted on said circular member and against which said connecting rod abuts, and in one relative position of said circular member and disc serving to hold the connecting rod and piston extended for minimum combustion space, and another position permitting th connecting rod and piston to assume a positiontfor maximum combustion :space, each cam being in the form of a disc having :a concaved area at one side, the connecting rods being engageable with this concaved area on one of the relative positions of said circular member and disc, and means mounted at the ends of said radial slots for varying the distances through which said elements may travel.

.9. .A device :for varying the combustion space 10 of a multi-cylinder engine, comprising a crank, a circular member on said crank, a disc free on said crank, and having a plurality of radial slots and frictionally connected with said circular member, ,a plurality of connecting rods for the-' pistons of said engine and having forked inner ends straddling the edge of said circular member and projecting elements engaging in said radial slots, means for relative partial rotation of said circular memberand disc, and a cam for each .connectin: rod mounted on said circular member and against which said connecting rod abuts,

and 'inaone. relative position of said circular member-and vdiscserving to hold the connecting rod and piston extended for minimum combustion spacmand another position permitting the connecting rod and piston to assume a position for maximum combustion space, each cam being in the form of a disc having a concaved area at one side, the connecting rods being engageable with this concaved area on on of the relative positions of said circular member and disc, and means mounted at the ends of said radial slots for varying the distances through which said elements may travel, said means comprising adjustment screws mounted on the ends of the slotsvand adaptedto be extended or retracted as required.

JOHN HLASNEY, JR. 

